The Earliest Signs

By Holly Korschun

Researchers at Marcus Autism Center, Children’s Healthcare of Atlanta, and Emory’s School of Medicine have identified signs of autism present in the first months of life.

The researchers followed babies from birth until age three, using eye-tracking technology to measure the way infants look at and respond to social cues. Infants later diagnosed with autism showed declining attention to the eyes of other people, from the age of two months onward. The results were reported in the advanced online publication of the journal Nature.

The study followed two groups of infants, one at low and one at high risk for having autism spectrum disorders. High-risk infants had an older sibling already diagnosed with autism, increasing the infant’s risk of also having the condition twentyfold. In contrast, low-risk infants had no first-, second-, or third-degree relatives with autism.

“By following these babies from birth, and intensively within the first six months, we were able to collect large amounts of data long before overt symptoms are typically seen,” says Warren Jones, director of research at Marcus Autism Center, assistant professor in the Department of Pediatrics, and the lead author on the study. Teams of clinicians assessed the children longitudinally and confirmed their diagnostic outcomes at age three. Then the researchers analyzed data from the infants’ first months to identify what factors separated those who received an autism diagnosis from those who did not.

What they learned was surprising. “We found a steady decline in attention to other people’s eyes, from two until twenty-four months, in infants later diagnosed with autism,” says coinvestigator Ami Klin, director of Marcus Autism Center and chief of the Division of Autism and Related Disorders in the Department of Pediatrics.

Differences were apparent even within the first six months, which has profound implications. “First, these results reveal that there are measurable and identifiable differences present already before six months. And second, we observed declining eye fixation over time, rather than an outright absence. Both these factors have the potential to dramatically shift the possibilities for future strategies of early intervention.”

Although the results indicate that attention to others’ eyes is already declining by two to six months in infants later diagnosed with autism, attention to others’ eyes does not appear to be entirely absent. If infants were identified at this early age, interventions could more successfully build on the levels of eye contact that are present.